This invention is directed toward the field of measurement, marking, and scoring (or cutting) as practiced in professions such as sewing, carpentry and metalworking. It is very important to achieve accurate and repeatable measurement with minimum potential injury to the person making the measurement. More specifically, this invention is related to the field of encased, extendible and self-retracting tape measuring devices.
U.S. Pat. No. RE 36,887 is incorporated into this application by reference and is directed toward the safety and accuracy issue. U.S. Pat. No. RE 36,887 describes an extendible tape measure where a finger guard and marking assist is provided for situations where the tape measure is used to slide along a surface during measuring and/or marking. A marker holder assist is described at the hook or zero end of the tape, but it does not provide for the variable dimensions of markers in its design and marker dimension must therefore be compensated in use of the marker holder assist. A measurement index is a line perpendicular to the direction of extension of the tape which is easily referenced to a series of measurement markings on the tape. No provision of a measurement index or marking assistance located at the measured distance along the tape is mentioned.
U.S. patent application 20010042315 for an extendible tape measure is incorporated into this application by reference and is directed toward providing a measurement marker assist on the zero end of the tape for sliding measurements with compensation for the thickness of a standard size pencil or marking device, but does not provide a finger guard.
Tape measuring devices with digital readouts and printed indicia are known and are included in the background for this invention.
There is still a need for an extendible tape measurement device to provide for finger protection and marking/scoring accuracy assistance. The point where this is most needed is near the exit point of the tape from the case. The reference point or points of measurement provided by this invention in respect to the extended tape will be called a measurement index throughout this application.